There are several good calculators out there to help you determine how many calories you should eat. They are just a guideline. Each of us is different and our experiences are different. A lot depends upon your activity level during the day, and other lifestyle and health factors.
At your weight, starting at 1800 a day and adjusting from there would be reasonable.
As far as exercise goes, I believe a well-rounded approach is best. Exercise not only helps with weight loss, but it helps tone and shape your body as you are losing. I alternated among cardio (dance, boxing, and walking), strength (weights and stretchy bands), core (stability ball and mat), and flexibility (yoga, and pilates). I used DVDs and my Wii (Wii Fit, My Fitness Coach, Gold's Gym Cardio Workout) along with walking. It has worked very well for me